Published by Actually Sleeping · Reviewed by Dr. Samantha Abrahamson, PharmD · Review policy · Updated 2026-11-10

Sleep at 21 months: what’s normal, what’s hard, and when to get help

At 21 months, the AASM recommends 11 to 14 hours per 24 hours, including naps. Most toddlers take one nap, and dropping it entirely is rare: a large review found fewer than 2.5% of children stop napping before age 2. Nap refusal, bedtime stalling and early waking are the usual complaints, and they are usually phases rather than signs your child has outgrown sleep.

What is changing at 21 months

Your toddler is heading toward the CDC’s 2-year milestones: running, kicking a ball, walking up a few stairs, saying two words together like “more milk”, and noticing when someone else is upset. Imagination and understanding are growing fast, which can bring new worries at bedtime.

The AAP says separation anxiety usually fades during the last half of the second year and around the second birthday, so many families see it easing now.

Nap strike or real readiness	What the research says
Children who stop napping before age 2	Fewer than 2.5% (Staton 2020)
Average naps per day, 1 to 2 years	1.2 (Galland 2012)
Average nap time, 1 to 2 years	About 2.3 hours among children who nap (Staton 2020)
Children who have stopped napping by age 3	About one in three (Staton 2020)

So a 21 month old refusing the nap has almost certainly not outgrown it.

Nap strikes, stalling and early starts at this age usually travel together, and handling one in isolation tends to make another worse. Actually Sleeping looks at your toddler’s whole day and night, and Dr. Sam writes one plan for it, with daily 1:1 check-ins.

What is normal at night

Studies of children 1 to 2 years recorded an average of 0.7 night wakings, with up to about 2.5 within the normal range, and a longest stretch averaging 8.3 hours across 6 to 24 months. An occasional night waking at 21 months is ordinary. Several every night is the kind of pattern Actually Sleeping helps families change.

What parents find hardest

Nap refusal that lasts a week or two, which makes it tempting to drop a nap your child still needs.
Bedtime stalling. One more book, one more drink.
Early waking. Morning light, nap length and an early start to the day can all play a part.
A new sibling or move. Big changes often show up at bedtime first.

Safe sleep at 21 months

Keep the crib while it is safe. Move out at 35 inches (89 cm) tall, when the rail is below about three-quarters of your child’s height, or once your toddler can climb out (AAP, MedlinePlus).
Install operable window guards above the first floor and keep climbable furniture away from windows (AAP).
Anchor dressers and bookshelves.

Night feeds

Most toddlers this age do not need milk at night, but your pediatrician decides that for your child. If they agree it can change, follow their advice on how; a sleep plan works around it.

When to talk to the pediatrician

Snoring most nights, mouth breathing, or pauses in breathing.
Daytime sleepiness, trouble paying attention or behavior problems that might be linked to poor sleep. The AAP lists these among sleep apnea signs.
Few words, not combining any words as 2 approaches, or loss of skills your child had.
Night terrors that keep happening.

Where to go from here

What drives a nap strike, a stalled bedtime or a 5 a.m. start is different for every toddler. Actually Sleeping works out what is driving yours and writes the plan around it, with bootcamp-style coaching before night one. We guarantee that your baby will sleep 8–12 hours through the night within 14 days of consistent, correct implementation of your sleep plan. Parents share results on our 12 months and up reviews. Related: early morning waking, the 18-month to 2-year schedule, and false starts at bedtime. Book a free consultation with Dr. Sam to start.

Want this fixed for your baby?

Actually Sleeping is 1:1 coaching: a sleep plan written for your baby by Dr. Sam, bootcamp-style coaching before the first night, and daily check-ins until it is working. 700+ families coached, 129 video reviews, and a written guarantee: 8–12 hours through the night within 14 days, or a full refund.

Book your free consultation → See what families say

Frequently asked

My 21 month old refuses the nap. Is the nap over?

Very unlikely. A systematic review found fewer than 2.5% of children stop napping before age 2, and about one in three has stopped by age 3. A nap strike at 21 months usually means the day needs adjusting, which a Actually Sleeping plan does for your child.

How much should a 21 month old sleep?

The AASM recommends 11 to 14 hours per 24 hours, including naps, for children 1 to 2 years old. The AAP supports this range. Total sleep matters more than the exact split between nap and night.

Why does my toddler wake so early?

Common causes are morning light, a bedtime that is too early or too late, and a nap that is too long or too early. Which one applies differs by child, so Dr. Sam works it out from your toddler’s actual days and nights.